Re: [PATCH V2 1/3] dax/dm: disable testing on devices that don't support dax

Zorro Lang
2020-02-21T09:37:44Z

On Thu, Feb 20, 2020 at 03:06:30PM -0500, Jeff Moyer wrote:
> Move the check for dax from the individual target scripts into
> _require_dm_target. This fixes up a couple of missed tests that are
> failing due to the lack of dax support (such as tests requiring
> dm-snapshot).
>
> Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
> ---
> common/dmdelay | 5 -----
> common/dmerror | 5 -----
> common/dmflakey | 5 -----
> common/dmthin | 5 -----
> common/rc | 11 +++++++++++
> 5 files changed, 11 insertions(+), 20 deletions(-)
>
> diff --git a/common/dmdelay b/common/dmdelay
> index f1e725b9..66cac1a7 100644
> --- a/common/dmdelay
> +++ b/common/dmdelay
> @@ -7,11 +7,6 @@
> DELAY_NONE=0
> DELAY_READ=1
>
> -echo $MOUNT_OPTIONS | grep -q dax
> -if [ $? -eq 0 ]; then
> - _notrun "Cannot run tests with DAX on dmdelay devices"
> -fi
> -
> _init_delay()
> {
> local BLK_DEV_SIZE=`blockdev --getsz $SCRATCH_DEV`
> diff --git a/common/dmerror b/common/dmerror
> index 426f1e96..7d12e0a1 100644
> --- a/common/dmerror
> +++ b/common/dmerror
> @@ -4,11 +4,6 @@
> #
> # common functions for setting up and tearing down a dmerror device
>
> -echo $MOUNT_OPTIONS | grep -q dax
> -if [ $? -eq 0 ]; then
> - _notrun "Cannot run tests with DAX on dmerror devices"
> -fi
> -
> _dmerror_setup()
> {
> local dm_backing_dev=$SCRATCH_DEV
> diff --git a/common/dmflakey b/common/dmflakey
> index 2af3924d..b4e11ae9 100644
> --- a/common/dmflakey
> +++ b/common/dmflakey
> @@ -8,11 +8,6 @@ FLAKEY_ALLOW_WRITES=0
> FLAKEY_DROP_WRITES=1
> FLAKEY_ERROR_WRITES=2
>
> -echo $MOUNT_OPTIONS | grep -q dax
> -if [ $? -eq 0 ]; then
> - _notrun "Cannot run tests with DAX on dmflakey devices"
> -fi
> -
> _init_flakey()
> {
> local BLK_DEV_SIZE=`blockdev --getsz $SCRATCH_DEV`
> diff --git a/common/dmthin b/common/dmthin
> index 7946e9a7..61dd6f89 100644
> --- a/common/dmthin
> +++ b/common/dmthin
> @@ -21,11 +21,6 @@ DMTHIN_POOL_DEV="/dev/mapper/$DMTHIN_POOL_NAME"
> DMTHIN_VOL_NAME="thin-vol"
> DMTHIN_VOL_DEV="/dev/mapper/$DMTHIN_VOL_NAME"
>
> -echo $MOUNT_OPTIONS | grep -q dax
> -if [ $? -eq 0 ]; then
> - _notrun "Cannot run tests with DAX on dmthin devices"
> -fi
> -
> _dmthin_cleanup()
> {
> $UMOUNT_PROG $SCRATCH_MNT > /dev/null 2>&1
> diff --git a/common/rc b/common/rc
> index eeac1355..65cde32b 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -1874,6 +1874,17 @@ _require_dm_target()
> _require_sane_bdev_flush $SCRATCH_DEV
> _require_command "$DMSETUP_PROG" dmsetup
>
> + echo $MOUNT_OPTIONS | grep -q dax
> + if [ $? -eq 0 ]; then
> + case $target in
> + stripe|linear|log-writes)

I've checked all cases which import ./common/dm.* (without dmapi), they all
has _require_dm_target. So this patch is good to me.

And by checking current linux source code:

0 dm-linear.c 226 .direct_access = linear_dax_direct_access,
1 dm-log-writes.c 1016 .direct_access = log_writes_dax_direct_access,
2 dm-stripe.c 486 .direct_access = stripe_dax_direct_access,
3 dm-target.c 159 .direct_access = io_err_dax_direct_access,

Only linear, stripe and log-writes support direct_access.

Thanks,
Zorro

> + ;;
> + *)
> + _notrun "Cannot run tests with DAX on $target devices."
> + ;;
> + esac
> + fi
> +
> modprobe dm-$target >/dev/null 2>&1
>
> $DMSETUP_PROG targets 2>&1 | grep -q ^$target
> --
> 2.19.1
>